The rules were squeezed quite a bit to fit 8 pages. Normally, we would say something lawyerly about last to pass through with an attack-capable unit. In this case, it is sort left to you to fill in the blanks. Sorry about any confusion!
No worries. So far, whenever I ask a rules question here on this forum. Some good soul replies within half an hour. It's pretty remarkable.
Overall I think the rules are very well written for OCS.